Methods: This prospective study included a total of 25 patients (14 males, 11 females; median age: 67 years; range, 23 to 75 years) who underwent erector spinae plane block categorized as the American Society of Anesthesiologists Class III and underwent off-pump coronary artery bypass grafting between June 01, 2020 and March 01, 2021. The effects of erector spinae plane block on the diameters and cross-sectional areas of the left and right internal mammary arteries and radial arteries were assessed using ultrasonography images taken both before and 45 min after the procedure, from the third, fourth, and fifth intercostal spaces for the left and right internal mammary arteries and from 3 cm proximal to the wrist for the radial arteries.

Results: The diameters and cross-sectional areas of the left and right internal mammary arteries and radial arteries significantly increased compared to baseline values after the erector spinae plane block (p<0.05). There was no significant difference in the pre- and post-procedural heart rate and mean arterial pressure values (p>0.05).

Conclusion: The bilateral erector spinae plane block, which was performed at the T5 level, provided vasodilatation of the left and right internal mammary arteries and radial arteries without causing any significant difference in the heart rate and mean arterial pressure. These findings indicate that the sympathetic block produced by the erector spinae plane block may facilitate better surgical conditions by preventing arterial spasms. Thus, bilateral erector spinae plane block may be a promising technique to achieve regional anesthesia for off-pump coronary artery bypass grafting.